Developing EST-SSR markers to study molecular diversity in Liriope and Ophiopogon Gang Li a , Won-Hee Ra a , Jae-Wan Park a , Soon-Wook Kwon a, b , Jung-Hoon Lee c , Chung-Berm Park c , Yong-Jin Park a, b, * a Department of Plant Resources, College of Industrial Science, Kongju National University, Yesan 340-702, Republic of Korea b Legume Bio-Resource Center of Green Manure (LBRCGM), Kongju National University, Yesan 340-702, Republic of Korea c Department of Herbal Crop Research, National Institute of Horticultural and Herbal Science, RDA, Suwon 369-873, Republic of Korea article info Article history: Received 25 May 2011 Accepted 13 August 2011 Available online 18 September 2011 Keywords: Liriope Ophiopogon EST-SSR Identification Genetic diversity Population structure abstract Twenty-two EST-SSR loci for further genetic analysis of Liriope and Ophiopogon species were developed by analyzing of 545 ESTs in Ophiopogon japonicus cDNA library and used to assess genetic diversity and population structure in 68 Liriope and Ophiopogon accessions (Liriope platyphylla, Liriope spicata, O. japonicus, and Ophiopogon jaburan). Among the 22 SSR loci, the di-nucleotide motif was the most prevalent, with a ratio of 56%, and AG/GA was the most common among di-nucleotide repeats, accounting for 42%. The polymorphic analysis showed a broad genetic background with an average genetic diversity index of 0.46. A model-based STRUCTURE analysis revealed the presence of three subpopulations, which was basically consistent with clustering based on the genetic distance. These newly developed EST-SSR markers will be useful for further studies such as taxonomy and molecular breeding studies and will further enhance our scientific understanding of the population genetic and conservation of Liriope and Ophiopogon. Ó 2011 Elsevier Ltd. All rights reserved. 1. Introduction Liriope and Ophiopogon are commonly and abundantly distributed in subtropical and temperate regions, China, Korea, Japan, and India. Liriope includes about eight species and Ophiopogon includes about 54 species. The two genera are closely related and vegetatively similar (Dai and Liang, 1991). Steroidal glycosides in the tubers of Liriope (Wang et al., 2011) are widely used to treat many diseases, such as myocardial ischemia and thrombosis, hypoxia, and senility, and to reduce gly- caemia (Kako et al., 1995). Additionally, liriopogons (Liriope, Ophiopogon) show a strong resistance to environmental pollution and have become popular and economically important groundcovers and borders. Thus, liriopogons possess considerable potential for commercial application. Despite their horticultural and medicinal importance, molecular research on Liriope and Ophiopogon has lagged behind other species because of a limited number of molecular markers and little polymorphic information. Traditionally, Liriope taxonomy was based primarily on morphological data, identified by a combination of flower, leaf, and root system characteristics, resulting in a variety of taxonomic systems. Some of the confusion regarding the correct naming of these plants is due to the difficulty distinguishing them, leading to plant substitution, mislabeling of cultivars, and seedling invasion into cultivar stocks, resulting in cultivar degradation. Molecular studies on these species and cultivars will provide a large step forward, confirming morphological descriptions, but only a few genomic markers have been explored to date. Many studies have attempted to taxonomically distinguish * Corresponding author. Department of Plant Resources, College of Industrial Science, Kongju National University, Yesan 340-702, Republic of Korea. Tel.: þ82 41 330 1201; fax: þ82 41 330 1209. E-mail address: yjpark@kongju.ac.kr (Y.-J. Park). Contents lists available at SciVerse ScienceDirect Biochemical Systematics and Ecology journal homepage: www.elsevier.com/locate/biochemsyseco 0305-1978/$ – see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.bse.2011.08.012 Biochemical Systematics and Ecology 39 (2011) 241–252